US11193447B2 - Piston and cylinder of an internal combustion engine and internal combustion engine - Google Patents

Piston and cylinder of an internal combustion engine and internal combustion engine Download PDF

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Publication number
US11193447B2
US11193447B2 US17/002,679 US202017002679A US11193447B2 US 11193447 B2 US11193447 B2 US 11193447B2 US 202017002679 A US202017002679 A US 202017002679A US 11193447 B2 US11193447 B2 US 11193447B2
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United States
Prior art keywords
piston
top land
abrasion
cylinder
internal combustion
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US17/002,679
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US20210062753A1 (en
Inventor
Talat Shaer
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MAN Energy Solutions SE
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MAN Energy Solutions SE
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/10—Pistons  having surface coverings
    • F02F3/12—Pistons  having surface coverings on piston heads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/28—Other pistons with specially-shaped head
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/10—Pistons  having surface coverings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P3/00—Liquid cooling
    • F01P3/06—Arrangements for cooling pistons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/004—Cylinder liners
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/0084—Pistons  the pistons being constructed from specific materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/16—Pistons  having cooling means
    • F02F3/20—Pistons  having cooling means the means being a fluid flowing through or along piston
    • F02F3/22—Pistons  having cooling means the means being a fluid flowing through or along piston the fluid being liquid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J1/00—Pistons; Trunk pistons; Plungers
    • F16J1/01—Pistons; Trunk pistons; Plungers characterised by the use of particular materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F2001/006—Cylinders; Cylinder heads  having a ring at the inside of a liner or cylinder for preventing the deposit of carbon oil particles, e.g. oil scrapers

Definitions

  • the invention relates to a piston of a cylinder of an internal combustion engine, to a cylinder of an internal combustion engine and to an internal combustion engine.
  • a piston of a cylinder of an internal combustion engine which is moveably guided, up and down, in a cylinder liner.
  • a flame ring is positioned in a recess of the cylinder liner.
  • grooves are introduced which accommodate the piston rings.
  • the radial outer surface of the piston forms a so-called top land, wherein the flame ring of the cylinder liner serves, among other things, for scraping off deposits from the radially outer surface of the piston, in particular in the region of the top land.
  • a clearance is necessary in order to make possible undisturbed moving of the piston in the cylinder liner.
  • a so-called waste volume forms, in which a fuel mixture can collect, which participates in the combustion only ineffectively.
  • the clearance between the piston and the flame ring is selected, according to the prior art, as small as possible. This requires high manufacturing tolerances.
  • a piston having a top land comprises or carries a soft, non-abrasion-proof coating.
  • the coating can be locally removed to exactly set the clearance necessary for operation between piston and flame ring, namely without demanding high manufacturing tolerances.
  • the non-abrasion-proof coating the waste volume between piston and flame ring can be minimized and the engine efficiency increased.
  • the non-abrasion-proof coating consists of resin-bonded graphite.
  • Such a coating is particularly preferred in order to set, during the engine operation, the clearance necessary for the operation between piston and flame ring by local abrasion of the coating.
  • the non-abrasion-proof coating has a thickness between 0.02 mm and 0.2 mm, preferentially between 0.05 mm and 0.15 mm. This thickness of the non-abrasion-proof coating is particularly preferred in order to set during the engine operation, the clearance between piston and flame ring necessary for the operation.
  • the invention relates to an internal combustion engine, an internal combustion engine comprises at least one cylinder.
  • FIG. 1 is a cross section in the form of an extract through a first cylinder according to the invention of an internal combustion engine according to the invention.
  • FIG. 2 is a cross section in the form of an extract through a second cylinder according to the invention of an internal combustion engine according to the invention.
  • FIG. 1 shows an extract of a cylinder 10 of an internal combustion engine according to the invention as per a first exemplary embodiment of the invention in the region of a cylinder liner 11 , and of a piston 12 that is moveably guided, up and down, in the cylinder liner 11 .
  • the piston 12 has a radially outer surface 13 and a front or upper piston crown 14 .
  • a trough 15 can be centrally introduced.
  • the piston 12 comprises grooves 16 a , 16 b and 16 c .
  • Piston rings 17 a , 17 b , 17 c are inserted into these grooves 16 a , 16 b and 16 c , respectively of the piston 12 .
  • the two upper piston rings 17 a , 17 b are referred to as compression rings and the lower piston ring 17 c as an oil scraper ring.
  • a top land 18 of the piston 12 extends between the piston crown 14 and the uppermost or front-most groove 16 a of the piston 12 .
  • the distance between the uppermost or front-most groove 16 a of the piston 12 and the piston crown 14 c is referred to as top land height 18 h of the top land 18 .
  • the cylinder liner 11 accommodates a flame ring 19 .
  • the flame ring 19 is inserted into a recess 20 of the cylinder liner 11 .
  • the piston 12 can be cleaned in the region of its top land 18 with the help of the flame ring 19 .
  • the flame ring 19 serves for scraping off deposits, such as, for example, coke, from the radially outer surface 13 of the piston 12 in the region of the top land 18 and thus in the region of the top land height 18 h.
  • an outer diameter of the radially outer surface 13 conically decreases in the region of the top land 18 , seen from the front-most or uppermost groove 16 a , in the direction of the piston crown 14 , at least in regions.
  • a free space 21 is formed, which determines the clearance between the flame ring 19 and the top land 18 of the piston 12 .
  • fuel can collect during engine operation, which is only inefficiently combusted. For this reason, this free space 21 is also referred to as a waste volume.
  • the top land 18 carries a non-abrasion-proof coating 22 radially outside.
  • This relatively soft, non-abrasion-proof coating 22 can be removed during a local contact between the top land 18 and the flame ring 19 , to thereby set the clearance necessary for operation between the top land 18 of the piston 12 and the flame ring 19 to a minimum during the engine operation. This increases the efficiency of the engine.
  • the non-abrasion-proof coating 22 is preferentially a coating of resin-bonded graphite.
  • the piston 12 is preferentially a piston assembled from a piston lower part that is not shown and a piston upper part, wherein piston lower part and piston upper part can both consist of steel or cast iron, in particular spheroidal graphite cast iron. Light metal can also be utilized.
  • the non-abrasion-proof coating 22 consists of a softer material than the material of the piston lower part and of the piston upper part. Furthermore, the non-abrasion-proof coating 22 consists of a softer material than the flame ring 19 and the cylinder liner 11 .
  • Non-abrasion-proof coating 22 Further properties of the non-abrasion-proof coating 22 are a temperature resistance up to 250° C., a resistance to attacks by fuel and lubricating oil, and a good adhesion/bonding.
  • the hardness of the coating 22 preferably is in a hardness range from 10-50 HB (Brinell). Soft materials such as, for example, resin-bonded graphite or heat-resistant plastics satisfy these properties.
  • the non-abrasion-proof coating 22 of preferentially resin-bonded graphite preferentially has a thickness between 0.02 mm and 0.2 mm, preferably between 0.05 mm and 0.15 mm.
  • the non-abrasion-proof coating 22 is applied to that region of the top land 18 , which, emanating from the uppermost or front-most groove 16 a , conically tapers in the direction of the piston crown 14 .
  • the coating 22 is applied to this region over its entire axial extent or over its entire axial length. Accordingly, the coating 22 in FIG. 1 ends in the region of the piston crown 14 .
  • FIG. 2 shows a modification of the invention in which the non-abrasion-proof coating 22 is configured shorter and ends at a distance from the piston crown 14 .
  • the piston 12 according to the invention is an oil-cooled piston.
  • the invention does not only relate to the piston 12 as such but rather also to a cylinder 10 with a cylinder liner 11 and a piston 12 according to the invention, as well as an internal combustion engine having at least one, preferentially multiple, such cylinder/s 10 .
  • the invention can be employed both with diesel internal combustion engines and also with spark-ignition gas engines as well as dual-fuel engines, namely both with two-stroke and also with four-stroke internal combustion engines.
  • the invention is employed in particular with pistons of large engines such as diesel engines or gas engines or diesel-gas engines on ships, the outer diameter of which is in particular in the range between 100 mm and 600 mm.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)
  • Cylinder Crankcases Of Internal Combustion Engines (AREA)
US17/002,679 2019-08-27 2020-08-25 Piston and cylinder of an internal combustion engine and internal combustion engine Active US11193447B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019122878.6A DE102019122878A1 (de) 2019-08-27 2019-08-27 Kolben und Zylinder einer Brennkraftmaschine und Brennkraftmaschine
DE102019122878.6 2019-08-27

Publications (2)

Publication Number Publication Date
US20210062753A1 US20210062753A1 (en) 2021-03-04
US11193447B2 true US11193447B2 (en) 2021-12-07

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
US17/002,679 Active US11193447B2 (en) 2019-08-27 2020-08-25 Piston and cylinder of an internal combustion engine and internal combustion engine

Country Status (7)

Country Link
US (1) US11193447B2 (de)
EP (1) EP3786437B1 (de)
JP (1) JP2021032253A (de)
KR (1) KR20210025484A (de)
CN (1) CN112443419A (de)
DE (1) DE102019122878A1 (de)
FI (1) FI3786437T3 (de)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA3226191A1 (en) 2021-08-04 2023-02-09 Wolfgang Fimml Cylinder liner for an internal combustion engine and a method of producing the same
JP2023091625A (ja) 2021-12-20 2023-06-30 株式会社ジャパンエンジンコーポレーション ピストンおよび舶用内燃機関

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4113773A1 (de) 1990-07-23 1992-01-30 Alcan Gmbh Kolben fuer verbrennungsmotoren
US5122226A (en) * 1987-08-12 1992-06-16 United Technologies Corporation Method of making hybrid composite structures of fiber reinforced glass and resin matrices
DE4240050A1 (de) 1992-11-28 1994-06-01 Mahle Gmbh Kolben-Zylinder-Vorrichtung eines Verbrennungsmotors
US5486299A (en) * 1993-11-02 1996-01-23 Dow Corning Asia, Ltd Wear-resistant lubricant composition
EP2243940A1 (de) 2009-04-06 2010-10-27 Wärtsilä Schweiz AG Reduziereinrichtung zur Reduzierung eines Gasdrucks auf ein Kolbenringpaket einer Hubkolbenbrennkraftmaschine
DE102013009415A1 (de) 2013-06-05 2014-12-11 Man Diesel & Turbo Se Kolben einer Brennkraftmaschine
US20160273483A1 (en) * 2015-03-17 2016-09-22 Toyota Jidosha Kabushiki Kaisha Piston for internal combustion engine, internal combustion engine including this piston, and manufacturing method of this piston
US20180179644A1 (en) * 2016-11-04 2018-06-28 Cummins Inc. Pistons with thermal barrier coatings
US20180216524A1 (en) * 2015-11-20 2018-08-02 Federal-Mogul Llc Combustion engine components with dynamic thermal insulation coating and method of making and using such a coating
US20190257265A1 (en) * 2018-02-21 2019-08-22 Federal-Mogul Llc Coating to reduce coking deposits on steel pistons
US10443537B2 (en) * 2015-12-28 2019-10-15 Tenneco Inc. Piston including a composite layer applied to a metal substrate

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DE3407405C1 (de) * 1984-02-29 1985-09-19 Goetze Ag, 5093 Burscheid Kolben fuer Brennkraftmaschinen
US5435872A (en) * 1991-11-01 1995-07-25 Decc Technology Partnership Sized coated pistons
DE4310491A1 (de) * 1993-03-31 1994-10-06 Mahle Gmbh Hubkolben eines Verbrennungsmotors mit einer zumindest teilweisen Laufflächenbewehrung
DE4312804A1 (de) * 1993-04-20 1995-02-16 Mahle Gmbh Tauchkolben für Verbrennungsmotoren
JP2599472Y2 (ja) * 1993-05-31 1999-09-06 株式会社ユニシアジェックス 内燃機関用ピストン
US5469777A (en) * 1994-07-05 1995-11-28 Ford Motor Company Piston assembly having abradable coating
DE19734053A1 (de) * 1997-08-06 1999-02-11 Alcan Gmbh Bestandteil, wie Kolben oder Zylinderkopf, eines Verbrennungsmotors und Verfahren zu dessen Herstellung
JP2006152981A (ja) * 2004-12-01 2006-06-15 Riken Corp 溶射ピストンリング及びその製造方法
JP2007064133A (ja) * 2005-09-01 2007-03-15 Nissan Diesel Motor Co Ltd ピストン構造
DE102007044106A1 (de) * 2007-09-15 2009-03-19 Mahle International Gmbh Zweiteiliger Kolben für einen Verbrennungsmotor
US9562491B2 (en) * 2012-04-20 2017-02-07 International Engine Intellectual Property Company, Llc. Carbon scraping ring with abradable coating
JP2014227859A (ja) * 2013-05-20 2014-12-08 トヨタ自動車株式会社 内燃機関のピストン

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5122226A (en) * 1987-08-12 1992-06-16 United Technologies Corporation Method of making hybrid composite structures of fiber reinforced glass and resin matrices
DE4113773A1 (de) 1990-07-23 1992-01-30 Alcan Gmbh Kolben fuer verbrennungsmotoren
DE4240050A1 (de) 1992-11-28 1994-06-01 Mahle Gmbh Kolben-Zylinder-Vorrichtung eines Verbrennungsmotors
US5560283A (en) * 1992-11-28 1996-10-01 Mahle Gmbh Piston-Cylinder assembly of an internal combustion engine
US5486299A (en) * 1993-11-02 1996-01-23 Dow Corning Asia, Ltd Wear-resistant lubricant composition
EP2243940A1 (de) 2009-04-06 2010-10-27 Wärtsilä Schweiz AG Reduziereinrichtung zur Reduzierung eines Gasdrucks auf ein Kolbenringpaket einer Hubkolbenbrennkraftmaschine
DE102013009415A1 (de) 2013-06-05 2014-12-11 Man Diesel & Turbo Se Kolben einer Brennkraftmaschine
US20160273483A1 (en) * 2015-03-17 2016-09-22 Toyota Jidosha Kabushiki Kaisha Piston for internal combustion engine, internal combustion engine including this piston, and manufacturing method of this piston
US20180216524A1 (en) * 2015-11-20 2018-08-02 Federal-Mogul Llc Combustion engine components with dynamic thermal insulation coating and method of making and using such a coating
US10443537B2 (en) * 2015-12-28 2019-10-15 Tenneco Inc. Piston including a composite layer applied to a metal substrate
US20180179644A1 (en) * 2016-11-04 2018-06-28 Cummins Inc. Pistons with thermal barrier coatings
US20190257265A1 (en) * 2018-02-21 2019-08-22 Federal-Mogul Llc Coating to reduce coking deposits on steel pistons

Also Published As

Publication number Publication date
EP3786437A1 (de) 2021-03-03
CN112443419A (zh) 2021-03-05
FI3786437T3 (fi) 2024-05-20
US20210062753A1 (en) 2021-03-04
KR20210025484A (ko) 2021-03-09
JP2021032253A (ja) 2021-03-01
EP3786437B1 (de) 2024-03-13
DE102019122878A1 (de) 2021-03-04

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